The recorders will be taken to Washington for examination later in the day.

Flames in the plane's tail section kept officials from accessing the flight data and cockpit voice recorders in the first 24 hours after the crash. But firefighters tamed the flames to the point where officials could start reaching the devices, the Birmingham mayor's office said.

"The fire ... has actually created quite an issue for getting to the recorders because it's all burned down, so we'll have to use shovels and picks to be able to sort of sift through that to get to them," said NTSB spokesman Robert Sumwalt.

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The devices could help investigators determine why the plane -- which Sumwalt said did not issue a distress call -- went down early Wednesday while on approach to the Birmingham-Shuttlesworth International Airport.

The Airbus A300-600F broke into pieces -- killing the pilot and a co-pilot -- as it crashed around 4:45 a.m. in an open field near a street that runs parallel to the airport. The majority of the debris was spread over an area of about 300 yards, Sumwalt said Wednesday.

Witnesses said the plane, which took off from Louisville, Kentucky, flew low over a neighborhood, striking the tops of trees and knocking down power lines as it crashed.

The crash site is about a half-mile north of a runway, FAA spokeswoman Kathleen Bergen told CNN.

Witness Peter Torres, a Civil Air Patrol member who said he is a former airline mechanic, said he thought he heard what sounded like a backfire from the jet&apos;s engines as the plane passed overhead. He rushed to his window.

"I saw the flash" of an apparent explosion, he said, followed by a "boom" that shook his home.

Airport neighbor Sharon Wilson told WBRC the plane seemed lower than usual for flights into the airport and sounded like it was sputtering as it flew overhead.

"We heard this loud boom, like, jump up out of your bed," she told the station.

"It was extremely low," she said. And then it sounded like it was sputtering, like it was out of fuel."

The plane was one of two flights UPS sends to Birmingham each day, company spokesman Mike Mangeot told CNN affiliate WBRC.

The crew did not report any trouble, Birmingham Mayor William Bell said, citing conversations with control tower officials. Light showers and a visibility of 10 miles were reported in the area of the airport at the time of the crash, according to CNN meteorologist Dave Hennen.

The plane that crashed Wednesday was built in 2003 and had 11,000 hours in the air spread over 6,800 flights, Airbus said in a news release.

Only UPS and FedEx fly the A300 in the United States, according Airbus. While it was once used for commercial passenger flights in the United States, the plane is now used only for cargo flights. UPS has 53 of the planes, Airbus said.

Wednesday's crash is the second involving an A300 in the United States. In 2001, an American Airlines A300 crashed in the Belle Harbor neighborhood of Queens, in New York City, shortly after takeoff from John F. Kennedy International Airport.

All 260 people on board that plane, as well as five people on the ground, were killed.

Wednesday's crash comes nearly three years after UPS's last major incident, the crash of a Boeing 747 in Dubai, United Arab Emirates, that killed two crew members.

Investigators traced the crash to a large fire in the cargo hold, which included a number of flammable lithium batteries, according to the country's General Civil Aviation Authority.

In 2006, a McDonnell Douglas DC-8 flown by UPS caught fire after landing at Philadelphia International Airport. Three crew members on the plane evacuated with minor injuries, according to NTSB records. Most of the cargo was destroyed.